What are the best sounding engines ever built - production, racing, modified, I don't care!

I have 2 choices that I am torn between...

Entry 1: 1966 Honda Rc149 - a 125cc 2-stroke inline 5-cylinder with a redline of 20,000... built in 1966. These things made monster power for their size, but had no power spread - this required an insane 8-speed gear box to make it anywhere close to rideable.

Entry 2: Mazda 787B - Rotary goodness, no introduction needed.

Also- the NSR500 makes me drool.

Best Engine Sounds of All Time?S